package com.example.demo;


import java.util.Random;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

/**
 * @author ChenXiaoBin
 * on 2020-09-06
 */
public class T1ReadWriteLock {

    static ReadWriteLock readWriteLock = new ReentrantReadWriteLock();

    private static int value;
    static Lock readLock = readWriteLock.readLock();
    static Lock writeLock = readWriteLock.writeLock();

    public static void read(Lock lock) {
        try {
            lock.lock();
            Thread.sleep(1000);
            System.out.println("read over");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }finally {
            lock.unlock();
        }

    }


    public static void write(Lock lock, int v) {
        try {
            lock.lock();
            Thread.sleep(1000);
            value = v;
            System.out.println("read over");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }finally {
            lock.unlock();
        }

    }

    public static void main(String[] args) {
        Runnable readR = ()-> read(readLock);
        Runnable writeR = ()->write(writeLock, new Random().nextInt());

        for (int i = 0; i < 18; i++) {
            new Thread(readR).start();
        }

        for (int i = 0; i < 2; i++) {
            new Thread(writeR).start();
        }
    }
}
